By-pass valve metering system
CA 2113390 A1 · Owner: Johnston, Douglas · Inventors: Johnston, Douglas
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A by-pass valve metering system for praying agricultural chemicals to the soil from a driver-operated moving vehicle through nozzles substantially independent of pump pressure. The system has a by-pass valve which is driver presetable prior to spraying. The by-pass valve is driver adjustable while the vehicle is moving for increasing or decreasing nozzle flow. Indicating means readable by the driver from the moving vehicle during praying indicates spray rate through the nozzles as a percentage of pump flow.
Read the whole patent
Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed January 13, 1994. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended January 13, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 13, 2016.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.